<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="https://unpkg.com/vue@3/dist/vue.global.js"></script>
</head>
<body>


<div id="app">{{ message }}
    <p>{{ message }}</p>
    <div>
        {{message}}
    </div>

</div>

<script>
    const {createApp, ref} = Vue

    createApp({
        setup() {

            let message = ref('Hello vue!')
            // 经过ajax请求
            let a = 4;
            message = a;

            return {
                message
            }
        }
    }).mount('#app')

    // let element = document.getElementById("app");
    // element.innerText = 1;
    // // 经过ajax请求 省略
    // let a = 2;
    // element = document.getElementById("app");
    // element.innerText = a;


</script>
</body>
</html>